A spatial tsunami hit Voyager 1
The spatial tsunami occurs when our parent star emits coronal mass ejection, throwing out a large amount of magnetic plasma from its surface. The one recorded in February is the longest shockwave ever studied by Voyager and the effects are still being felt today.
NASA’s Voyager 1, launched in 1977 and in interstellar space since 2012, is still under the effect of the last shock wave that struck last February, as shown by the data sent to Earth. In fact, the space probe (one of the first to venture in the exploration of the boundaries of the Solar System) has recorded three shock waves, one of which (to April 2013) confirmed to the NASA researchers the entry into interstellar space August 25, 2012 by exceeding the heliopause, that is the extreme limit of our planetary system within which the solar winds are blocked by the interstellar medium. The rings of plasma encountered by Voyager 1 were 40 times denser than those previously measured. This was critical to state that the probe had crossed the frontier of interstellar space. The spacecraft of NASA, which also has a twin Voyager 2, is the man-made object currently more distant in the Solar System: it is, in fact, to 130 astronomical units from the Sun (about 20 billion kilometers). Both probes have carried out the mission of the Voyager flyby around Jupiter and Saturn. Voyager 2, launched after Voyager1, has also passed close to Uranus and Neptune, but has not yet reached interstellar space.
The spatial tsunami recorded in February is the shockwave longest ever studied by Voyager. Shock waves recorded by the instruments on board have shown that if we were with a ship in interstellar space, the journey could be more than busy, contrary to the imaginary space of calm and quiet. The data were presented at the American Geophysical Union meeting in San Francisco.
When this happens, the shock waves? The head is the Sun, as always happens in our system. They occur when our parent star emits coronal mass ejection, throwing out a large amount of magnetic plasma from its surface. This generates a pressure wave (just like a tsunami on Earth) and it rolls into the interstellar plasma – charged particles present in the space between the stars – it creates a shock wave that disrupts the plasma. “The spatial tsunami causes the ionized gas that is out there to vibrate like a bell,” said Ed Stone, Voyager mission scientist at the California Institute of Technology in Pasadena.
We said that this is the third shock wave detected. The first, however, occurred between October and November 2012 and the second between April and May 2013 (when there was a quantity of plasma even higher). The probe, over the last year, has ground a good distance (about 400 million kilometers). Researchers are trying to understand why the effects of this third spatial tsunami are still perceptible, and claim that these shock waves propagate very far into space, probably twice the distance between the Sun and the probe.